<template>
  <div class="detail">
    <Header/>
    <div class="main">
      <div class="course-info">
        <div class="wrap-left">
          <video-player
            class="video-player vjs-custom-skin"
            ref="videoPlayer"
            :playsinline="true"
            :options="playerOptions"
            @play="onPlayerPlay($event)"
            @pause="onPlayerPause($event)">
          </video-player>
        </div>
        <div class="wrap-right">
          <h3 class="course-name">{{course.name}}</h3>
          <p class="data">{{course.students}}人在学&nbsp;&nbsp;&nbsp;&nbsp;共{{course.lessons}}课时/{{course.lessons === course.pub_lessons?'更新完成':`已更新${course.pub_lessons}课时`}}&nbsp;&nbsp;&nbsp;&nbsp;难度：{{course.get_level_display}}</p>
          <div class="sale-time" v-if="course.discount_name">
            <p class="sale-type">{{course.discount_name}}</p>
            <p class="expire">
              距离结束：
              仅剩 {{course.active_time/60/60/24 | format_time}}天
              {{course.active_time/60/60%24 | format_time}}小时
              {{course.active_time/60%60 | format_time}}分
              <span class="second">{{course.active_time%60 | format_time}}</span> 秒
            </p>
          </div>
          <p class="course-price">
            <span v-if="course.discount_name">活动价</span>
            <span class="discount">¥{{course.active_real_price}} 元</span>
            <span class="original" v-if="course.discount_name">¥{{course.price}} 元</span>
          </p>
          <div class="buy">
            <div class="buy-btn">
              <button class="buy-now">立即购买</button>
              <button class="free">免费试学</button>
            </div>
            <div class="add-cart" @click="AddCart">
              <img src="static/image/gouwuche.png" alt="">
              加入购物车
            </div>
          </div>
        </div>
      </div>
      <div class="course-tab">
        <ul class="tab-list">
          <li :class="tabIndex==1?'active':''" @click="tabIndex=1">详情介绍</li>
          <li :class="tabIndex==2?'active':''" @click="tabIndex=2">课程章节
            <span :class="tabIndex!=2?'free':''">(试学)</span>
          </li>
          <li :class="tabIndex==3?'active':''" @click="tabIndex=3">用户评论 (42)</li>
          <li :class="tabIndex==4?'active':''" @click="tabIndex=4">常见问题</li>
        </ul>
      </div>
      <div class="course-content">
        <div class="course-tab-list">
          <div class="tab-item" v-if="tabIndex==1">
            <div v-html="course.brief_html"></div>
          </div>
          <div class="tab-item" v-if="tabIndex==2">
            <div class="tab-item-title">
              <p class="chapter">课程章节</p>
              <p class="chapter-length">共11章 147个课时</p>
            </div>
            <div class="chapter-item" v-for="(value, index) in course.chapter_list" :key="index">
              <p class="chapter-title"><img src="/static/image/1.svg" alt="">第{{value.chapter}}章·{{value.name}}</p>
              <ul class="lesson-list">
                <li class="lesson-item" v-for="(lesson, lesson_index) in value.lesson" :key="lesson_index">
                  <p class="name"><span class="index">第{{lesson.lesson}}课时</span>{{lesson.name}}<span class="free">免费</span></p>
                  <p class="time">{{lesson.duration}}<img src="/static/image/chapter-player.svg"></p>
                  <button class="try">立即试学</button>
                </li>
              </ul>
            </div>
          </div>
          <div class="tab-item" v-if="tabIndex==3">
            用户评论
          </div>
          <div class="tab-item" v-if="tabIndex==4">
            常见问题
          </div>
        </div>
        <div class="course-side">
          <div class="teacher-info">
            <h4 class="side-title"><span>授课老师</span></h4>
            <div class="teacher-content">
              <div class="cont1">
                <img :src="course.teacher.image">
                <div class="name">
                  <p class="teacher-name">{{course.teacher.name}}</p>
                  <p class="teacher-title">{{course.teacher.title}}</p>
                </div>
              </div>
              <p class="narrative">{{course.teacher.brief}}</p>
            </div>
          </div>
        </div>
      </div>
    </div>
    <Footer/>
  </div>
</template>

<script>
  import Header from "./common/Header"
  import Footer from "./common/Footer"

  export default {
    name: "Detail",
    data() {
        return {
          tabIndex: 2,
          course_id: 0, // 课时id
          course: {
            teacher: {}
          },
          // 视频播放配置
          playerOptions: {
            playbackRates: [0.7, 1.0, 1.5, 2.0],  //播放速度
            autoplay: false, //如果true,则自动播放
            muted: false, // 默认情况下将会消除任何音频。
            loop: false, // 循环播放
            preload: 'auto',  // 建议浏览器在<video>加载元素后是否应该开始下载视频数据。auto浏览器选择最佳行为,立即开始加载视频（如果浏览器支持）
            language: 'zh-CN',
            aspectRatio: '16:9', // 将播放器置于流畅模式，并在计算播放器的动态大小时使用该值。值应该代表一个比例 - 用冒号分隔的两个数字（例如"16:9"或"4:3"）
            fluid: true, // 当true时，Video.js player将拥有流体大小。换句话说，它将按比例缩放以适应其容器。
            sources: [
               // 播放资源和资源格式
              {
                // 视频资源格式
                type: "video/mp4",
                //你的视频地址（必填）
                src: "http://img.ksbbs.com/asset/Mon_1703/05cacb4e02f9d9e.mp4"
              }
            ],
            poster: "../static/image/course-cover.jpeg", //视频封面图
            width: document.documentElement.clientWidth, // 默认视频全屏时的最大宽度
            notSupportedMessage: '此视频暂无法播放，请稍后再试', //允许覆盖Video.js无法播放媒体源时显示的默认信息。
          }
        }
    },
    methods: {
      // 检查访问的连接是否符合要求
      get_course_id(){
        let course_id = this.$route.params.id;
        course_id = parseInt(course_id);
        console.log(course_id);
        if (course_id > 0){
          this.course_id = course_id;
        }else {
          let self = this;
          this.$alert(
            '参数有误！，别乱搞！！！',
            {
            callback() {
              self.$router.go(-1); // 返回上一页面
            }
          })
        }
      },

      // 向后端发送请求，获取课时详情页所需要的数据。
      get_course_detail (){
        this.$axios.get(
          `${this.$settings.Host}/course/detail/${this.course_id}/`
        ).then(
          response => {
            this.course = response.data;
            this.playerOptions.sources[0].src = response.data.course_video;
            this.playerOptions.poster = response.data.course_img;
            if (this.course.active_time > 0) {
              let timer = setInterval(
                () => {
                  if (this.course.active_time){
                    this.course.active_time--;
                  }else{
                    clearInterval(timer);
                  }
                },
                1000
              )
            }
          }
        ).catch(
          error => {
            console.log(error.response.data);
          }
        )
      },

      // 当视频播放时，执行的方法
      onPlayerPlay(event){
        this.$message.success("关闭广告");
      },
      // 当视频暂停时，执行的方法
      onPlayerPause(event){
        this.$message.error("显示广告");
      },

      // 验证用户是否登录
      check_user_login(){
        let token = localStorage.user_token || sessionStorage.user_token;
        if (!token) {
          let self = this;
          this.$confirm('对不起您尚未登录，请登录后再添加商品！', '路飞学城', {
            confirmButtonText: '确定',
            cancelButtonText: '取消'
          }).then(
            () => {
              self.$router.push('/login/');
            }
          );
          return false;
        }
        return token;
      },

      // 添加到购物车
      AddCart(){
        // 先要验证用户是否登录
        let token = this.check_user_login();

        // 将课程id发送到后端
        if (!token) {
          // 如果token为false，AddCart函数不执行
          return false;
        }
        this.$axios.post(
          `${this.$settings.Host}/cart/`,
          {
            course_id: this.course_id,
          },
          {
            headers: {
              'Authorization': 'jwt ' + token,
            }
          }
        ).then(
          response => {
            // console.log(response.data);
            this.$message.success(response.data.msg);
            let course_len = response.data.course_len;
            this.$store.commit('add_cart', course_len);
          }
        ).catch(
          error => {
            // console.log(error.response.data);
            this.$message.success(error.response.data.msg);
          }
        )
      },
    },
    filters: {
      format_time(val){
        let timer_val = parseInt(val);
        if (timer_val < 10) {
          timer_val = `0${timer_val}`
        }
        return timer_val
      }
    },
    created() {
        // 课程ID
        this.get_course_id();
        this.get_course_detail();
      },
    components: {
          Header,
          Footer,
      }
  }
</script>

<style scoped>
  .main {
    background: #fff;
    padding-top: 30px;
  }

  .course-info {
    width: 1200px;
    margin: 0 auto;
    overflow: hidden;
  }

  .wrap-left {
    float: left;
    width: 690px;
    height: 388px;
    background-color: #000;
  }

  .wrap-right {
    float: left;
    position: relative;
    height: 388px;
  }

  .course-name {
    font-size: 20px;
    color: #333;
    padding: 10px 23px;
    letter-spacing: .45px;
  }

  .data {
    padding-left: 23px;
    padding-right: 23px;
    padding-bottom: 16px;
    font-size: 14px;
    color: #9b9b9b;
  }

  .sale-time {
    width: 464px;
    background: #fa6240;
    font-size: 14px;
    color: #4a4a4a;
    padding: 10px 23px;
    overflow: hidden;
  }

  .sale-type {
    font-size: 16px;
    color: #fff;
    letter-spacing: .36px;
    float: left;
  }

  .sale-time .expire {
    font-size: 14px;
    color: #fff;
    float: right;
  }

  .sale-time .expire .second {
    width: 24px;
    display: inline-block;
    background: #fafafa;
    color: #5e5e5e;
    padding: 6px 0;
    text-align: center;
  }

  .course-price {
    background: #fff;
    font-size: 14px;
    color: #4a4a4a;
    padding: 5px 23px;
  }

  .discount {
    font-size: 26px;
    color: #fa6240;
    margin-left: 10px;
    display: inline-block;
    margin-bottom: -5px;
  }

  .original {
    font-size: 14px;
    color: #9b9b9b;
    margin-left: 10px;
    text-decoration: line-through;
  }

  .buy {
    width: 464px;
    padding: 0px 23px;
    position: absolute;
    left: 0;
    bottom: 20px;
    overflow: hidden;
  }

  .buy .buy-btn {
    float: left;
  }

  .buy .buy-now {
    width: 125px;
    height: 40px;
    border: 0;
    background: #ffc210;
    border-radius: 4px;
    color: #fff;
    cursor: pointer;
    margin-right: 15px;
    outline: none;
  }

  .buy .free {
    width: 125px;
    height: 40px;
    border-radius: 4px;
    cursor: pointer;
    margin-right: 15px;
    background: #fff;
    color: #ffc210;
    border: 1px solid #ffc210;
  }

  .add-cart {
    float: right;
    font-size: 14px;
    color: #ffc210;
    text-align: center;
    cursor: pointer;
    margin-top: 10px;
  }

  .add-cart img {
    width: 20px;
    height: 18px;
    margin-right: 7px;
    vertical-align: middle;
  }

  .course-tab {
    width: 100%;
    background: #fff;
    margin-bottom: 30px;
    box-shadow: 0 2px 4px 0 #f0f0f0;

  }

  .course-tab .tab-list {
    width: 1200px;
    margin: auto;
    color: #4a4a4a;
    overflow: hidden;
  }

  .tab-list li {
    float: left;
    margin-right: 15px;
    padding: 26px 20px 16px;
    font-size: 17px;
    cursor: pointer;
  }

  .tab-list .active {
    color: #ffc210;
    border-bottom: 2px solid #ffc210;
  }

  .tab-list .free {
    color: #fb7c55;
  }

  .course-content {
    width: 1200px;
    margin: 0 auto;
    background: #FAFAFA;
    overflow: hidden;
    padding-bottom: 40px;
  }

  .course-tab-list {
    width: 880px;
    height: auto;
    padding: 20px;
    background: #fff;
    float: left;
    box-sizing: border-box;
    overflow: hidden;
    position: relative;
    box-shadow: 0 2px 4px 0 #f0f0f0;
  }

  .tab-item {
    width: 880px;
    background: #fff;
    padding-bottom: 20px;
    box-shadow: 0 2px 4px 0 #f0f0f0;
  }

  .tab-item-title {
    justify-content: space-between;
    padding: 25px 20px 11px;
    border-radius: 4px;
    margin-bottom: 20px;
    border-bottom: 1px solid #333;
    border-bottom-color: rgba(51, 51, 51, .05);
    overflow: hidden;
  }

  .chapter {
    font-size: 17px;
    color: #4a4a4a;
    float: left;
  }

  .chapter-length {
    float: right;
    font-size: 14px;
    color: #9b9b9b;
    letter-spacing: .19px;
  }

  .chapter-title {
    font-size: 16px;
    color: #4a4a4a;
    letter-spacing: .26px;
    padding: 12px;
    background: #eee;
    border-radius: 2px;
    display: -ms-flexbox;
    display: flex;
    -ms-flex-align: center;
    align-items: center;
  }

  .chapter-title img {
    width: 18px;
    height: 18px;
    margin-right: 7px;
    vertical-align: middle;
  }

  .lesson-list {
    padding: 0 20px;
  }

  .lesson-list .lesson-item {
    padding: 15px 20px 15px 36px;
    cursor: pointer;
    justify-content: space-between;
    position: relative;
    overflow: hidden;
  }

  .lesson-item .name {
    font-size: 14px;
    color: #666;
    float: left;
  }

  .lesson-item .index {
    margin-right: 5px;
  }

  .lesson-item .free {
    font-size: 12px;
    color: #fff;
    letter-spacing: .19px;
    background: #ffc210;
    border-radius: 100px;
    padding: 1px 9px;
    margin-left: 10px;
  }

  .lesson-item .time {
    font-size: 14px;
    color: #666;
    letter-spacing: .23px;
    opacity: 1;
    transition: all .15s ease-in-out;
    float: right;
  }

  .lesson-item .time img {
    width: 18px;
    height: 18px;
    margin-left: 15px;
    vertical-align: text-bottom;
  }

  .lesson-item .try {
    width: 86px;
    height: 28px;
    background: #ffc210;
    border-radius: 4px;
    font-size: 14px;
    color: #fff;
    position: absolute;
    right: 20px;
    top: 10px;
    opacity: 0;
    transition: all .2s ease-in-out;
    cursor: pointer;
    outline: none;
    border: none;
  }

  .lesson-item:hover {
    background: #fcf7ef;
    box-shadow: 0 0 0 0 #f3f3f3;
  }

  .lesson-item:hover .name {
    color: #333;
  }

  .lesson-item:hover .try {
    opacity: 1;
  }

  .course-side {
    width: 300px;
    height: auto;
    margin-left: 20px;
    float: right;
  }

  .teacher-info {
    background: #fff;
    margin-bottom: 20px;
    box-shadow: 0 2px 4px 0 #f0f0f0;
  }

  .side-title {
    font-weight: normal;
    font-size: 17px;
    color: #4a4a4a;
    padding: 18px 14px;
    border-bottom: 1px solid #333;
    border-bottom-color: rgba(51, 51, 51, .05);
  }

  .side-title span {
    display: inline-block;
    border-left: 2px solid #ffc210;
    padding-left: 12px;
  }

  .teacher-content {
    padding: 30px 20px;
    box-sizing: border-box;
  }

  .teacher-content .cont1 {
    margin-bottom: 12px;
    overflow: hidden;
  }

  .teacher-content .cont1 img {
    width: 54px;
    height: 54px;
    margin-right: 12px;
    float: left;
  }

  .teacher-content .cont1 .name {
    float: right;
  }

  .teacher-content .cont1 .teacher-name {
    width: 188px;
    font-size: 16px;
    color: #4a4a4a;
    padding-bottom: 4px;
  }

  .teacher-content .cont1 .teacher-title {
    width: 188px;
    font-size: 13px;
    color: #9b9b9b;
    white-space: nowrap;
  }

  .teacher-content .narrative {
    font-size: 14px;
    color: #666;
    line-height: 24px;
  }
</style>
